//The MIT License

//Copyright (c) 2009 Lluis Sanchez, Nick Darnell

//Permission is hereby granted, free of charge, to any person obtaining a copy
//of this software and associated documentation files (the "Software"), to deal
//in the Software without restriction, including without limitation the rights
//to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
//copies of the Software, and to permit persons to whom the Software is
//furnished to do so, subject to the following conditions:

//The above copyright notice and this permission notice shall be included in
//all copies or substantial portions of the Software.

//THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
//IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
//FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
//AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
//LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
//OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
//THE SOFTWARE.

using System;
using System.Reflection.Emit;

namespace Polymorph
{
    /// <summary>
    /// The <see cref="CodeAssignment"/> class represents an assignment '=' operation.
    /// </summary>
    public class CodeAssignment : CodeExpression
    {
        private CodeValueReference m_var;
        private CodeExpression m_exp;

        public CodeAssignment(CodeValueReference var, CodeExpression exp)
        {
            m_exp = exp;
            m_var = var;
        }

        public override void Generate(ILGenerator gen)
        {
            m_var.GenerateSet(gen, m_exp);
            m_exp.Generate(gen);
        }

        public override void GenerateAsStatement(ILGenerator gen)
        {
            CodeExpression val = m_exp;
            if (m_var.ResultType == typeof(object) && m_exp.ResultType.IsValueType)
                m_var.GenerateSet(gen, new CodeCast(typeof(object), m_exp));
            else
                m_var.GenerateSet(gen, m_exp);
        }

        public override void PrintCode(CodeWriter cp)
        {
            m_var.PrintCode(cp);
            cp.Write(" = ");
            m_exp.PrintCode(cp);
        }

        public override Type ResultType
        {
            get { return m_var.ResultType; }
        }
    }
}